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CDC Resources for Pandemic Flu

An influenza pandemic can occur when a non-human (novel) influenza virus gains the ability for efficient and sustained human-to-human transmission and then spreads globally. Influenza viruses that have the potential to cause a pandemic are referred to as ‘influenza viruses with pandemic potential.’

Examples of influenza viruses with pandemic potential include avian influenza A (H5N1) and avian influenza H7N9, which are two different “bird flu” viruses. These are non-human viruses (i.e., they are novel among humans and circulate in birds in parts of the world) so there is little to no immunity against these viruses among people. Human infections with these viruses have occurred rarely, but if either of these viruses was to change in such a way that it was able to infect humans easily and spread easily from person to person, an influenza pandemic could result.

CDC’s pandemic preparedness efforts include ongoing surveillance of human and animal influenza viruses, risk assessments of influenza viruses with pandemic potential, and the development and improvement of preparedness tools that can aid public health practitioners in the event of an influenza pandemic.

The links below offer more information about influenza pandemics and highlight some of CDC Influenza Division’s continued work on influenza pandemic preparedness.

CDC Influenza Division International Program works with a wide range of international partners, including the World Health Organization, national ministries of health and others to build capacity to respond to pandemics and to prevent and control seasonal influenza.